1. Field of the Invention
The present invention relates generally to agricultural field tillage implements and their method of use, and more particularly to a one-pass tillage implement for preparing a seedbed for planting which eliminates soil density changes for greater root development, improved plant health and greater yields.
2. Background of the Invention
A properly prepared seedbed is essential for good crop yields. There are various types of tillage implements currently being used by crop producers for seedbed preparation. Most tillage implements used for seedbed preparation utilize traditional soil working tools such as discs, sweeps or shanks, alone or in combination, in varying arrangements. While each of these different soil working tools performs the intended purpose for which they were designed, most tillage implements which utilize the above mentioned traditional soil working tools actually hinder proper root development, which in turn results in poorer plant health and lower crop yields.
For example, traditional field cultivator implements with traditional cultivator sweeps lift and fluff the top three to four inches of soil, leaving an untilled xe2x80x9cfloorxe2x80x9d below that depth. As the roots begin to emerge and grow in the three to four inches of loose top soil, the early roots are able to grow larger in diameter. However, as the crop root system continues to develop, these larger diameter roots eventually begin to hit the denser soil of the untilled floor. Unable to penetrate the denser soil of the floor, the larger diameter roots travel along the floor of the tillage layer seeking a crack or a path in which to grow deeper. Eventually, the larger diameter roots are forced to grow smaller in diameter in order to enter the cracks and penetrate the more dense soil of the floor. Thus, crops that are planted in seedbeds prepared by traditional soil working tools and methods are more susceptible to wind damage since the crops are anchored in the deeper soil by only a few smaller diameter roots that managed to penetrate the floor or enter cracks in the floor.
Therefore, it is desirable to provide a seedbed with uniform soil density throughout the entire depth of the root system. When roots develop in a seedbed with uniform density, the roots will maintain their diameter and grow down rather than out along a tillage layer. Roots that grow deeper while maintaining their diameter not only create a stronger anchor to resist wind damage, but result in improved plant health and greater yields.
While an ideal situation may be a seedbed of less dense soil throughout the entire root zone, it is inefficient and impractical to till the soil deep enough to ensure a uniform soil density throughout the root zone of most crops. In addition, even if such a tillage system was available, in order to till the soil at such depths, the soil conditions would have to be ideal. Unfortunately, due to weather patterns and the limited time frame in which crops must be planted to ensure harvest before winter, producers do not have time to wait for ideal soil conditions before beginning planting.
Eliminating seedbed tillage is the ideal solution to creating a seedbed with uniform soil density. If the seedbed is not tilled, the emerging roots will develop through uniform soil density. Though the early roots developing in denser, untilled soils may not be as initially large as roots developing in tilled loose soil, these roots will maintain their diameter and grow down rather than along a tillage layer, thereby creating a stronger stand of crop able to resist wind damage. While it may be desirable to eliminate tillage of the seedbed altogether, it is often desirable, and at times even necessary, to cut, chop and redistribute surface crop residue remaining from the previous year""s crop and to break up the soil surface crust that develops over the winter months so that the soil starts to dry more rapidly and warm more quickly. This is true particularly in wet springs.
Based on the foregoing, it is evident that there is a need for an improved tillage implement which, in one-pass, will cut, chop and redistribute crop surface residue without tilling the soil at seed planting depths, but yet breaks up the hard crust at the soil surface and further provides a level soil surface ready for planting. A tillage implement manufactured by McFarlane Manufacturing Co., Inc., of Sauke City, Wis., known as the Spiral Reel Stalk Chopper provides at least some of these desirable features, but lacks a system to aggressively lift and distribute the chopped crop surface residue and to thoroughly break up the hard soil crust.
Specifically, the McFarlane tillage implement is a single-pass tillage implement. It includes spiral reel harrow assemblies comprised of five hardened steel blades to cut and chop heavy crop stubble at ground level. Additionally, because the spiral reel harrow only penetrates the top one or two inches of the soil surface, it does not till the soil at seed planting depths, thereby maintaining the desired uniform density of the soil at seed depth. Disposed behind the spiral reel harrow is a five-bar flexible spike-tooth harrow that is designed to stir, level and firm the soil loosened by the spiral reel. Disposed behind the spike-tooth harrow is a trailing leveling board to level the soil. Accordingly, the spiral reel of the McFarlane implement provides the desirable features of cutting and chopping the crop surface residue while maintaining uniform soil density at seed depth, and further provides a means to level the soil. However, the five-bar flexible spike-tooth harrow of the McFarlane implement fails to aggressively lift and distribute the chopped crop surface residue and to thoroughly break up the hard soil crust.
It is known that a xe2x80x9cprickle chainxe2x80x9d harrow or a xe2x80x9cspider wheelxe2x80x9d rotary harrow will aggressively lift and redistribute crop surface residue and will aggressively break up soil surface crusts. U.S. Pat. No. 5,000,270 and U.S. Pat. No. 5,794,712 disclose a tillage implement utilizing a prickle chain harrow. However, these and other prior art references fail to teach combining the advantages and features of a prickle chain harrow or a spider wheel rotary harrow with a crop surface residue chopping tool and a leveling tool.
Accordingly, there is a need for tillage tool which will chop crop surface residue, aggressively lift and redistribute the chopped surface crop residue, and then level the soil so that the soil surface is substantially smooth and ready for planting, all in a single-pass.
A preferred embodiment of the present invention is a one-pass field tillage implement comprising a wheeled frame having a longitudinal axis and a transverse axis and adapted to be pulled by a prime mover. The wheeled frame operably supports at least three longitudinally spaced tillage tool assemblies which will chop crop surface residue, aggressively lift and redistribute the chopped surface crop residue, and then level the soil so that the soil surface is substantially smooth and ready for planting, all in a single-pass.
The first tillage tool assembly is preferably a rotary spiral reel disposed substantially transverse to the longitudinal axis of the frame and adapted to cut and chop crop surface residue as the tillage implement is pulled through the field. The second tillage tool assembly is preferably a prickle chain harrow, or, alternatively a rotary spider wheel harrow disposed longitudinally rearward of the first tillage tool assembly and adapted to penetrate and loosen the upper soil layer crust and to aggressively lift and distribute the chopped crop residue on the soil surface as the tillage implement is pulled through the field. The third tillage tool assembly is preferably a leveling board disposed longitudinally rearward of the second tillage tool assembly and adapted to drag over the soil surface thereby leaving the soil surface substantially smooth and ready for planting.
To the accomplishment of the above objects, features and advantages, this invention may be embodied in the form illustrated in the accompanying drawings, attention being called to the fact, however, that the drawings are illustrative only, and the changes may be made in the specific form illustrated and described within the scope of the appended claims.